Deliverables Advanced methods for field spectrometry in terms of energy and angle The quantities to be determined for the radiation protection of workers, personal dose equivalent and effective dose, depend on the energy and the direction of the neutron radiation. Two prototype instruments of energy/direction spectrometers were developed for use in unknown radiation fields in nuclear industry. These are based on different measurement principles and complement each other. The reference values for energy- and direction-dependent quantities Hp(10) and E were calculated from these spectra. The direction spectrometer with superheated drop detectors uses a "telescope design" with a single superheated drop detector at the centre of a 30 cm diameter nylon-6 sphere. The direction spectrometer based on silicon detectors consists of six detector capsules, each containing a stack of 4 silicon detectors, mounted onto the surface of a 30 cm diameter polyethylene sphere. The response matrix of the full detector set-up was determined from measurements. While the development and validation of the first device is not complete, the second devices was used and tested in all radiation fields. Due to the restricted applications of these instruments and the considerable effort needed to transfer these into routine devices, exploitation in the form commercial devices does not appear imminent. The spectrometers are, however, available on request for investigations. Advanced personal dosemeters and area monitors for mixed radiation and results on their dosimetric and technical performance Results were obtained from a large number of dosimetric equipment including area monitors (Berthold LB 6411, Harwell Leake N91, Studsvik 2202, Wendi-2, SSI Sievert), active electronic personal dosemeters (Aloka PDM-313, PTB DOS-2002, Saphymo Saphydose n, Synodys DMC 2000 GN, Thermo Electron EPD-N, Thermo Electron EPD-N2) and other personal dosemeters (BTI PND and BDT, DIMNP HpSLAB, NRPB PADC, PSI CR-39, PSI DIS-N, Local TLD devices). These include commercial devices and instruments developed by the partners outside or within the project. The dosimetric and technical performance of the different instruments was published in the open literature. The area monitors yielded responses between 0.5 and 1.5, with a slight under-response in harder spectra. Despite the small underestimation in terms of H*(10), these instruments do provide generally conservative estimates of H(p)(10) or E. For the personal dosemeters, a significant spread of the results was observed. While the best results were obtained in hard spectra, many dosemeters over-responded significantly in soft spectra. The new active (electronic) personal dosemeters (APDs) do not generally give better results than passive ones in terms of the spread of responses - at least for the workplace fields investigated. APDs show, however, a much lower detection limit. Catalogue with neutron spectra based on reference spectrometry In total, seventeen different places were investigated: nuclear energy production (reactors), transport of the nuclear fuel (transport casks), fresh MOX fuel rods manufacturing and a site handling nuclear material. A catalogue with these spectra was published in the open literature. The measurements revealed significant differences in the neutron energy distributions at the workplaces. While all distributions exhibit similar structures - a thermal peak, a rather flat intermediate energy region and a peak from fast neutrons with a maximum between 100 keV and 1 MeV - the contributions of these neutrons to the fluence varies significantly. Reference values for personal dose equivalent and other radiation protection quantities Based on the spectrometric information collected in the different workplaces with mixed neutron-photon radiation, reference values for different radiation protection quantities (ambient dose equivalent, H*(10), personal dose equivalent, H(p)(10),and effective dose, E) were compiled. The results were published in the open literature. The reference method used to determine H*(10) of neutrons in unknown radiation fields was Bonner sphere (BS) spectrometry. BS spectrometry was chosen for this project because it is well established, it has been benchmarked against other methods, e.g. calculations, and it allows H*(10) to be determined with small uncertainties in the order of 5% (one relative standard uncertainty) provided that the response matrix of the spectrometer is known precisely and that data analysis is performed carefully. A reference method to determine H(p)(10) does not exist, yet. The direction spectrometers developed in this project are still research tools for which further validation is needed. The results from these instruments was improved by using angle integrated spectra from BS as pre-information. In this case, the uncertainties are in the order of 30%. The results were in agreement with those from transport calculations performed for simulated workplace fields and for workplace fields at the VENUS research reactor. Searching for OpenAIRE data... 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